jlleitschuh / hawt-app

Simplified assembly building and booting for simple flat classpath based apps

Hawt App

The Hawt App maven based build plugin makes it easy to create and launch simple java apps that use a flat classpath and a class with a main. It handles creating a tar.gz archive that contains all your app's runtime dependencies in the lib directory and creates a bin/run script that handles setting up your classpath in the right order and executing the process java.

Produced Artifacts

Using the build goal of this plugin will create the following:

• an unpacked assembly of the app in the target/hawt-app directory.
• a tar.gz archive of that assembly directory at: target/${project.artifactId}-${project.version}-app.tar.gz

If you want to test out launching your app, just execute the target/hawt-app/bin/run script.

Usage

You can use it on any maven module which contains a class that can be run from the CLI. You just need to let it know which main class to use. For example:

mvn package org.jboss.hawt.app:hawt-app-maven-plugin:1.2:build -Dhawt-app.main=org.apache.camel.cdi.Main

To create the app as part of you default build for the module, add the a plugin configuration similar to the following in your maven module:

<plugin>
  <groupId>org.jboss.hawt.app</groupId>
  <artifactId>hawt-app-maven-plugin</artifactId>
  <version>1.2</version>
  <executions>
    <execution>
      <goals>
        <goal>build</goal>
      </goals>
      <phase>package</phase>
    </execution>
  </executions>
  <configuration>
    <main>org.apache.camel.cdi.Main</main>
  </configuration>
</plugin>

Plugin Configuration Options

The following table contains the configuration properties you can set either in the plugin configuration or via a command line Maven property to adjust the results of the built application archive.

Name	Maven Property	Description
assembly	hawt-app.assembly	Directory where the application assembly will be created. Default: ${project.build.directory}/hawt-app
archive	hawt-app.archive	Archive file that will be created. Default: ${project.build.directory}/${project.artifactId}-${project.version}-app.tar.gz
archiveClassifier	hawt-app.archiveClassifier	The GAV classifier that will be assigned to the archive. Default: app
archivePrefix	hawt-app.archivePrefix	the path prefixed on the files within the archive. Default: ${project.artifactId}-${project.version}-app/
main	hawt-app.main	The main class that will be executed by the launch process.
source	hawt-app.source	If this directory exists, then it's contents are used to augment the contents of the application assembly. For example it could be used to add an etc/defaults script to setup environment variables. Default: ${basedir}/src/main/hawt-app

Env Configuration Options

There are several environment variables that can be set before running the bin\run script to customize your app's startup.

Environment Variable	Description
JVM_ARGS	Options that will be passed to the JVM. Use it to set options like the max JVM memory (-Xmx1G).
JVM_DEBUG_ARGS	JVM debug arguments
JVM_DEBUG	If set to true, then enables JVM debug on port 5005
JVM_AGENT	Set this to pass any JVM agent arguments for stuff like profilers
MAIN_ARGS	Arguments that will be passed to you application's main method. Default: the arguments passed to the bin/run script.

Runtime Defaults Configuration

If an ${APP_HOME}/etc/defaults file exists it will be sourced in by the run script and you can use this to set all the environment variables if you wish. You can additionally also modify the values of the following variables if you want to change the defaults.

Environment Variable	Description
MAIN	The main class that will be executed.
APP	The name of this app, if supported by your system this will be displayed as the process name. Default: ${project.artifactId}
CLASSPATH	The classpath of the java application